Heroin use and non-medical use of prescription opioid continue to be a Public Health problem. Young adults are an especially important group because of the high rates of current use of illicit drugs (19.7 %). Opiate addiction is considered a chronic and relapsing disorder, and while agonist maintenance treatment continues to be the most common treatment for opiate dependence, the strong evidence of beneficial effects are mostly during the substitution period, but not during the post-treatment period when relapse and risk of returning to previous patterns of drug use are high. Growing preclinical evidence strongly suggests that the co-administration of an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist such as memantine with an opioid agonist may facilitate the sustainability of the opioid agonist efficacy on the mu-opioid receptor while at the same time and same animal reduce the sensitization to short-acting opiates'reinforcing effects. The purpose of this pilot clinical trial is to examine to what extent the co-administration of memantine (15mg &30mg) to buprenorphine will improve treatment outcomes during and after treatment compared to buprenorphine alone. This 13-week clinical trial will provide treatment for 60 opioid dependent patients, aged 18-25 years, who will be randomized to three treatment conditions: (1) memantine 15mg/day + buprenorphine;(2) memantine 30mg/day + buprenorphine and (3) placebo + buprenorphine. The study will have an induction, maintenance and discontinuation phases. Baseline measures related to opioid use will be determined during the first week of treatment participation. Subjects'randomization will be balanced by severity of opioid dependence. All participants will participate in weekly group therapy. The primary outcomes will be weekly rates of self-reported use of opiates and urine toxicology during treatment with buprenorphine;rates of early relapse by self-report use of opiates and urine toxicology;and rates of side-effects and adverse events. The research proposed in this application is innovative because memantine enhanced time-limited buprenorphine therapy may become an effective alternative short-term intervention for many young adult patients. PUBLIC HEALTH RELEVANCE: Heroin use and non-medical use of prescription opioids among young adults continues to increase. Opiate addiction is considered a chronic and relapsing disorder that is effectively treated with long-term maintenance on agonist therapy. This treatment may not necessarily be the best treatment for young adults. This study is evaluating if adding memantine to buprenorphine may become an effective alternative short-term intervention for many young adult patients, and change current clinical practice for this population.